A patient suffering from polymorphous light eruption did not respond to conventional modes of therapy. Phototesting demonstrated that he was sensitive to light from 290 to 500 nm. The patient was treated with a combination of sulisobenzone and β-carotene, with amelioration of the disease.
Nordlund JJ, Klaus SN, Mathews-Roth MM, Pathak MA. New Therapy for Polymorphous Light Eruption. Arch Dermatol. 1973;108(5):710-712. doi:10.1001/archderm.1973.01620260058024